I have been programming with Basic for over 30 years. I have written stand alone applications with VB.NET. And .NET is OK for some applications. However I believe that AutoCAD needs VBA. I have written many successful VBA applications using AutoCAD, Word, Excel, and Access. Some mission critical VBA applications will be in danger of becoming obsolete without VBA. Also, Microsoft has seen the light and will continue to support VBA in their Office products.
I have been using VBA with AutoCAD since its first release in R14. At that time some Visual Basic (5 or 6) sample applications were also included with AutoCAD. VBA worked better for me, and I sure VB 5/6 worked better for others. Having multiple programming like, .NET, AutoLisp, VBA, etc. will make AutoCAD a more rounded product. Please do not limit our programming choices.